Compared with the controls, MetS cases had a statistically significant decrease of follicle-stimulating hormone (FSH) (SMD: −0.87, 95% CI: −1.53 to −0.21; I2 = 97%, n = 6), testosterone (SMD: −5.61, 95% CI: −10.90 to −0.31; I2 = 100%, n = 6), and inhibin B (SMD: −2.42, 95% CI: −4.52 to −0.32; I2 = 0%, n = 3) (Figures 5, 6). This evidence concerns the gene BRD2 and metabolic syndrome.